Salt for electrolytic rectifiers



a: teas. lin all- FRED W. EABHOFF, F HABTJFGRD, AND WILLIAM C. BROOKS, 01E MERIDEN, CON- NEGTIGUT, ASSIGNORS TO THE HARTFORD BATTERY MANUFACTURING COMPANY, @EE SQ'UTHINGTON, CONNECTICUT, A CORPORATEON OF CONNECTICUT.

WT F0153 ELECTROLYTIC RECTIFIEES.

lie Drawing. Application filed May 26, 1927. Serial Ito. 194,524.

This invention relates to those salts which it appears to act uniformly over the entire form the active agents of the electrolytes of surface of the tantalum rather than having current rectifiers and electrolytic condensers, a predominant action in spots or at the edges particularly such devices as employ tantalum of the electrode, as does the acid electrolyte 5 or silite electrodes as the valve metals. now commonly used.

The object of the invention is the produc- Another method that may be employed is tion of a chemical salt, with an acid content, to mix and boil in water approximately, w in a solid state but which is readily soluble ammonium sulphate, 100 parts, sulphuric in water, and is especially efiicient for use acid, up to 74 parts, and iron sulphate, or

W in connection with rectifiers and condensers equivalent 'double valent metallic sulphate, of the tantalum-lead or silite-lead electrode 6 parts, until excess water is eliminated. type, whereby the handling and transporta- This product may be cast in molds to form tion of electrolytes for such devices is faciliblocks or sticks, or allowed to crystallize, tated and the cost reduced. and it may be left for transportation in the 15 This object is attained by combining sulblock or stick form, or if quick solution is phuric acid with certain metallic salts and desired it may be ground or pulverized.

the radical ammonium, and reducing the It is common practice, in order to prevent resultant to a solid state, either in the form rapid evaporation and to eliminate danger or" blocks, rods, crystals, or powder, which of explosion, to place oil on top of the elec Jl may be shipped dry, and when desired for trolyte 01E chargers and electrolytic condensuse merely dissolved in water to provide the ers. For this purpose a small amount of required electrolyte. oil, may be mixed with the dry salt de 76 The salt which forms the subject oil this scribed herein. When water is added to disinvention being dry, is much less in weight solve the salt, the oil is liberated and floats and bulk than the commonly used liquid acid to the surface, forming the desired seal.

electrolyte, with a consequent reduction in It has been found that the salt above destorage space, freight, cartage and handling scrlbed regulates the charging rate better so charges, and being in a solid rather than 9. than the commonly used liquid sulphuric liquid state, all danger of leakage and oleacid solution, and does not increase the so structive acid corrosion is eliminated, a conharging rate to a dangerous point upon con dition which permits the salt electrolytic centration of the solution resulting from agent and complete rectifiers or electrolytic evaporation, as occurs with the liquid suls5 condensers, to be shipped through the mails phuric acid solution electrolyte at present or by other transport agency, in ordinary used.

packages, ready for use upon the mere ad- The inven ion claimed is dition of water for dissolving the salt. 1. A dry salt, needing only the addition @ne manner of attaining the desired end of water to form a complete electrolyte for is to combine, approximat ly, gra current rectifiers and electrolytic condensers monium sulphate, 40 grams ul hu i id, having tantalum or similar filming metal cc and 6 grams oi double valent metal, as ierelectrodes, which salt is chiefly composed rous or manganous sulphate. These ingrediam ni m bi-sulphate cats are mixed thoroughly and allowed to 2 A dry salt, needing only the addition as cool and solidify into crystalline masses. of W r to form a complete electrolyte for This product is then preferably ground or current rectifiers and electrolytic condensers pulverized, the final result "b ing a dry mizhaving tantalum or similar filming metal ture of normal ammonium sulphate and electrodes, which salt is composed oi amacid ammonium sulphate, with a slight con= monium lei-sulphate and a small amount of too tent oi double valent metal, that is readily double valent metal.

soluble in water, and when so liquefied pro 3. A dry salt, needing only the addition due-es an electrolyte which used in a r ctifier of water to form a complete electrolyte for or electrolytic condenser having a tantalum current rectifier-s electrolytic condensers electrode, is particularly eii'icient and is not having tantalum or similar filming metal destructive of the tantalum electrodes, which is composed of 2 I monium bi-sulphate and a small percentage of double valentmetal, and having a small quantity of oil mixed therein. 4. A dry salt, needing only the addition of water to form a complete electrolyte for current rectifiers and electrolytic condensers having tantalum or similar filming metal electrodes, composed of the radical ammonium, sulphuric acid and metallic salts.

5. A dry salt, needing only the addition of water to form a complete electrolyte for ourrent rectifiers and electrolytic condensers, composed of ammonium sulphate, sulphuric acid and ferrous sul hate.

6. A dry salt, nee of Water to form a complete electrolyte for current rectifie'rs of the tantalum-lead-sulphuricsacid type, composed of ammonium sulphate, sulphuric acid and sulphate of a double Valent metal.

- FRED W. BARHOFF.

WILLIAM C. BROOKS.

ing only the addition 15 

